This invention is in the field of information and communications, and is more specifically directed to improved processes, circuits, devices, and systems for encryption and decryption and other information and communication processing purposes, and processes of making them. Without limitation, the background is further described in connection with wireless communications processing.
Wireless communications, of many types, have gained increasing popularity in recent years. The mobile wireless (or “cellular”) telephone has become ubiquitous around the world. Mobile telephony has recently begun to communicate video and digital data, in addition to voice. Wireless modems, for communicating computer data over a wide area network, using mobile wireless telephone channels and techniques are also available.
Wireless data communications in wireless local area networks (WLAN), such as that operating according to the well-known IEEE 802.11 standard, has become especially popular in a wide range of installations, ranging from home networks to commercial establishments. Short-range wireless data communication according to the “Bluetooth” technology permits computer peripherals to communicate with a personal computer or workstation within the same room.
Encryption/decryption techniques are used to improve the security of retail and other business commercial transactions in electronic commerce and the security of communications wherever personal and/or commercial privacy is desirable. Security is important in both wireline and wireless communications.
Digital signal processing (DSP) chips and/or other integrated circuit devices are essential to these systems and applications. Reducing the cost of manufacture and increasing speed of operation without compromising performance is an important goal in DSPs, integrated circuits generally and system-on-a-chip (SOC) design. Cost of manufacture and power consumption usually decrease if the number of electronic logic circuits (gate count) can be reduced. Decreasing the gate count in the encryption/decryption circuit contributes to the goals of reduced cost of manufacture and power consumption. The importance of decreasing the gate count becomes even stronger in hand held/mobile applications where small size is so important, to control the cost and the power consumed.
Speed of operations is reflected in reduced initialization time of encryption and increased throughput of encrypted communications. Both initialization time and throughput are important considerations in communications and other applications. Reduced initialization time reduces delays in starting and continuing communications processes. Increased throughput allows more information to be communicated in the same amount of time, or the same information to be communicated in a shorter time. Communications security should contribute as little overhead, or burden, to communications as possible, all other system requirements being equal.
WEP (Wired Equivalent Privacy) encryption/decryption (RC4) is an example of one data transmission security method. Improved implementations for reduced gate count and increased speed are desirable in the art for data processing generally and for RC4 and other encryption/decryption processes for use at both ends of communications applications such as WLAN and cellular communications.
U.S. Pat. No. 6,549,622, D. P. Matthews, Jr., describes a system and method suggested to be a fast hardware implementation of RC4. U.S. Patent Application Publication 2002/0186839, Parker et al., describes an apparatus and method for cipher processing system using multiple port memory and parallel read/write operations and has a comparator circuit. Further alternative and more advantageous approaches would be desirable in the art.